The environment features a simple 4-joint walking robot. The goal is to achieve an average total return of at least 300 in a limited number of steps (but in general, higher is better, and you shouldn't stop at 300). The action space involves motor speed control for the robot's joints. Observations include various physical states like hull angle speed and leg contact with the ground. Rewards are given for forward movement, with penalties for falls and motor use. The starting state has the walker at the terrain's start, and episodes end if the hull contacts the ground or reaches the terrain end.